<template>
  <div>
    <router-link
      tag='div'
      to='/'
      class="header-abs"
      v-show='showAbs'
    >
      <div class="iconfont header-abs-back">&#xe624;</div>
    </router-link>
    <div
      class="header-fixed"
      v-show="!showAbs"
      :style="opacityStyle"
    >
      <router-link to='/'>
        <div class="iconfont header-fiexd-back">&#xe624;</div>
      </router-link>
      景点详情
    </div>
  </div>
</template>

<script type="text/ecmascript-6">
export default {
  name: 'DetailHeader',
  data () {
    return {
      showAbs: true,
      opacityStyle: {
        opacity: 0
      }
    }
  },
  components: {

  },
  methods: {
    handleScroll () {
      const top = document.body.scrollTop
      console.log(document.body.scrollTop)
      if (top > 60) {
        let opacity = top / 140
        opacity = opacity > 1 ? 1 : opacity
        this.opacityStyle = {
          opacity
        }
        this.showAbs = false
      } else {
        this.showAbs = true
      }
    }
  },
  activated () {
    window.addEventListener('scroll', this.handleScroll)
  },
  deactivated () {
    window.removeEventListener('scroll', this.handleScroll)
  }
}
</script>

<style scoped lang="stylus">
@import '~styles/varibles.styl'
.header-abs
  position: absolute
  left: .2rem
  top: .2rem
  width: .8rem
  height: .8rem
  line-height: .8rem
  text-align: center
  border-radius: .4rem
  background: rgba(0, 0, 0, 0.8)
  .header-abs-back
    color:#fff
    font-size: .4rem
 .header-fixed
    position: fixed
    z-index: 2
    top: 0
    left: 0
    right: 0
    height: $headerHeight
    line-height: $headerHeight
    text-align: center
    color: #ffffff
    background: $bgColor
    overflow: hidden
    font-size: .32rem
    .header-fiexd-back
      position: absolute
      width: .64rem
      text-align: center
      font-size: .4rem
      left: 0
      top: 0
      color: #fff
</style>
